Sylvania



'(NoModvel.) A v G'. P. PAYNE 8v. W. D. GHARKY.

TBLBPHQNE TRANSMITTER.-

Patented Mar. 22,1898.

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UNITE. STATES PATENT Fries'.

GEORGE F. PAYNE AND WILLIAM D. GHARKY, OF PHILADELPHIA, PENN- SYLVANIA; SAID GHARKY ASSIGNOR TO SAID PAYNE.

TELEPHONE-TRANSMITTER.

SPECIFICATION forming part of Letters Patent ivo. 600,991, dated March 22, 189s. Applicationned september 11, 1897. serial No. 651,286. (No modem To a/ZZ whom t may con/cern;- Be it known'that we, GEORGE F. PAYNE and WILLIAM D. GHARKY, vcitizens of the United States of America, residing in the city tions than has heretofore been practicable.

Various attempts have heretofore been made to increase the amplitude of the electrical vibrations produced bya transmitter; but in all cases of which we are aware the mechanism provided and having for its object toincrease the amplitude of the vibrations has been of sucha character asto avail itself only partly and in varying amount of the power of A the battery or other generator, and for this reason the electrical vibrations .necessarily differed to a considerable degree with the sound-vibrations.

The broad purpose of our invention is to provide an arrangement of electrodes in the transmitter which will be in ltheir operation upon the electrical current approximately similar to a pole-changing switch having two movable portions, and we accomplish this by providing four resistance -cells containing granular conducting material, electrically coupling said cells in pairs and connecting the coupling-conductors, then electrically coupling the cells in two other pairs the members of which are not coupled by the first conducting"connections, and, again connecting the second set of coupling-conductors, we place a battery in the connection between one set of couples and an induction-coil in the connection between the other set of couples, and we provide mechanical'connections from the diaphragm to the cells, whereby the vibra- 5o tions of the diaphragm simultaneously increase pressure on the material in one of each coupled pair of cells and relaxes the pressure on the other cells, as a result of which action the battery-current, following the lines of least resistance, is for the most part switched vin alternately opposite directions through the induction-coil connection.

In practice we have used two sets of electrode-faces, four in each and grouped to form the walls of four resistance-cells containing granular material, electrically coupling the faces of one set in pairs and ofthe other set also in pairs, but in such manner as not to couple the same cells coupled by the connections of the first set. One set of faces we secure in fixed position, while the other set is movable and mechanically connected to vibrate with the diaphragm, and our preferred construction is that shown, having three stationary electrode-buttons arranged one behind the other and the central ybutton having two faces, while the end buttons have each one inwardly-turned face and are wire-connected, the metal center of the central button serving to couple its two faces and a wire coupling it with the connection between the outer buttons. Two movable buttons, each having two faces coupled through their metal backs, are placed one on each side of the central button and wire connection made from one to the other, the battery and coil being connected as above described and the movable buttons attached to the diaphragm.

Reference being now had to the drawings in which our invention is illustrated, Figure l is a central longitudinal section through a transmitter including our invent-ion; Fig. 2, an enlarged sectional view of the electrodes of the transmitter; Fig. 3, a transverse section on the line l 1 of Fig. l; Figs. 4 and 5, diagrammatic illustrations of the operation -of our transmitter, and Figs. 6 and '7 diagrammatic comparative illustrations of a polechanging switch of analogous character.

A indicates the diaphragm of the transmitter, to the the center of which a nut A is secured.

B indicates the framing of the transmitter, and C an extension of the framing slotted, as indicated at C', and to which is secured the IOO box D, in which the electrodes are situated, E indicating a binding-screw working in the slot C and acting to hold the box D to the frame extension C.

F F indicate the heads of the box D.

G is the central stationary electrode, which we preferably construct of brass with carbon faces, as indicated at ll Il. The brass center of this electrode is grooved, as shown at G', for the purpose of engaging with a binding-screw l, which holds it in position and by which it is electrically connected with other parts of the apparatus. The outer stationary electrodes are each formed with stems, as indicated at J and K, which extend through the heads F F of the box and are secured in proper position by the set-screws ff. At the inner end of each rod is a brass disk, (indicated at J and K,) J 2 and K2 indicating brass disks screwing on the stems J and K and aeting to clamp a light felt washer L between themselves and the disks J' and K'. Said disks J and K are each provided with acarbon facing ll, as indicated. The movable electrodes, of which one is situated on each side of the central stationary electrode, are conveniently made up, as shown, of two brass disks, such as are indicated at M M and N N, a light felt washer L being clamped between the disks in each case. The electrode N is secured to the diaphragm by a light iron or steel rod O, one end OZ ot which is shown threaded and screwing into the elect-rode end, while the other end Oisthreaded and screws into the nut A. This rod is covered by a non-conducting jacket P, which in turn is partly inclosed by a conducting-tube Qwl1ich extends from a point on the rod lying outside of the hollow stem K to the point where the movable electrode Mis secured, said movable electrode being secured directly to this conducting-rod, which may conveniently be of brass, and the connection, as shown, through a threaded portion or head Q' of the brass tube. Outside of the brass tube isa protecting non-conducting jacket R.

It will be noticed that the brass tubing does not pass through the central stationary electrode, and that we have indicated the nonconducting jacket of the central rod as enlarged between the two movable electrodes, the enlarged portion being indicated at P.

It will be understood, of course, that gran ular material, preferably carbon as commonly used, is placed between each opposite pair of electrode-faces, there being thus four separate bodies of granular carbon, which are prevented from comin ginto physical contact with each other, or into electrical connection otherwise than through the electrodes, by the light felt washers L, the said washers also serving to support and center the electrodes.

It will be noticed that the carbon facings of the central electrode and ot the stationary electrode K through which the actuating-rod for the movable electrodes passes have chamfered edges to their perforations, making a nice flt with the rod which passes through, the purpose of this being to prevent the cntrance of the granular carbon beyond the carbon facing of the electrodes, and the niceness of t-he iit is to be determined by this purpose.

The two outer stationary electrodes are shown as connected together by wires U and U/, extending from their stems J and K. The connection ot' the outer electrodes with the central stationary electrode is shown as being made through a wire V, which extends from the connection U U to the screw I and connects through said screw with the central electrode. The connection between the movable electrodes is conveniently made, as indicated in Fig. 2, by wires T and T, connecting with the end Q2 of the brass tube Q and with the end O' of the central rod O.

XVe have indicated at W an induction-coil in the wire V and at X the coacting coil in the secondary line Y Y', and at S we have indicated a battery. It will be understood, of course, that the positions of the battery and induction-coil may be transposed, the operation remaining practically the saine.

The operation of our device can be readily followed from the diagrams Figs. 4 and 5, in connection with the pole-changing switch diagrams indicated in Figs. G and 7. As the movable electrodes are by the action of the diaphragm impelled toward the left the resistance to the passage of a current between the electrodes N and G and M and K is diminished, while it is increased as between the electrodes N and J and M and G. Consc- IOO quently the greater part of the battery-current will pass through the wire T', the movable electrode N, the stationary electrode G, upward through the wire connection V, thence through the wire connection U to the stationary electrode K, and thence through the movable electrode M and wire T to the battery. An impulse to the right, as indicated in Fig. reverses conditions, producing, as there shown, a downward current through the wire V, the changes from the one condition to the other being of course gradual and without sensible interruption, and the result being that practically the whole battery-current is made to follow with the utmost nicety vibrations of the diaphragm of the transmitter.

The diagram Figs. (5 and are simply supplied to show the familiar action of a polechauging switch with two movable members, and it will be noticed by comparing them with the diagrams Figs. i and 5 that the action is almost exactly parallel, the difference being simply that whereas the pole-chan ging switch interrupts the current abruptly the action of the transmitter-switch, as we may call it, produces no interruption.

Of course as electrical connection through any resistance-cell is never cut ol'f entirely there will be theoretically and no doubt in reality a division of current between the cells IOS IIO

of greater and lesser resistance; but we have found in practice and `for the purposes of the transmitter that practically the whole current follows the lines of least resistance and that the device operates in close analogy to the pole-changing switch. 4 l Y Our device, as shown, is capable of very many structural modifications -without departure from the spirit of our invention, and our claims are not, therefore, to be read as limited on any other features of construction than those expressly called for therein.

Having now described our invention, what we claim as new, and desire to secure by Letters Patent, is-

l. In a telephone-transmitter, a set of four resistance-cells containing granular conducting material, electrical connections coupling said cells in two pairs, an electrical connection between said pair connections, other electrical connections coupling said cells in two pairs the members of which are not connected bythe first-pair connections, an electrical connection between the second-pair connections, a battery and an induction-coil, one situated in the'connection between the one set of pairs and the other situated in the connection between the second set of pairs, and mechanical connections from the transmitterdiaphragm whereby the resistance of the cells is varied as described and so as to cause the greater part of the battery-current to traverse the induction-coil in alternately opposite directions.

2. In a telephone-transmitter, a set of four fixed electrode-faces in combination with a set of four electrode-faces attached to and movable with the diaphragm, said faces of the two sets of electrodes being arranged opposite to each other in pairs and so as to form walls of cells, the electrode-faces being so arranged that with each movement of the diaphragm two pairs will approach and two recede from each other, granular conducting material placed between each pair of coacting faces in the cell formed between them, electrical connections coupling on e set of faces in pairs, an electrical connection between said connections, electrical connections coupling the other set of faces inA pairs said coupled faces being those belonging to cells not coupled by the connections between the first set, an electrical connection between the connections last mentioned, and a battery and induction-coil one situated in the connection between the coupled faces of one vset and the other in theconnection between the coupled faces of the other set, all substantially as specified. v

3. In a telephone-transmitter the combination with a set of four fixed electrode-faces arranged parallel to and one behind the other with a set of four synchronously-movable electrode-faces arranged in line with the fixed faces and so as to form with them the walls of Yfour resistance-cells, granular conducting material held in each cell, electrical connections coupling the two outer and two inner electrode-faces of one set in pairs, and a connection between said pair connections, electrical connections coupling the outer and adjacent faces of the other set in pairs and a connection between said pair connections, a battery and an inductioncoil one situated in the one and the other in the othervconnection between the coupled pairs of faces aforesaid and mechanical means securing the movable electrodes with the transmitter-diaphragm so as to cause them to move therewith.

4. In a telephone-transmitter the combination of one set of electrodes, the outer ones having faces turned inward and the central one having two faces, andthe two outer ones electrically connected together and with the central electrode, of a second set of electrodes, one situated on each side of the central electrode, an electrical connection between said movable electrodes, means for securing one set of electrodes in place, means for connecting the other set of electrodes with the diaphragm so as to move therewith, abattery and an induction-coil, one situated in the connection leading to the central electrode and one in the connection between the set of two eleci trodes, all substantially as specified, and so as to alternate the greater part of the batterycurrent through the coil.

5. In a telephone-transmitter the combination of three stationary electrodes, the outer ones having faces turned inward and the centrai one having two faces, and the two outer ones electrically connected together and with the central electrode, of two movable electrodes actuated by the diaphragm and one situated on each side of the stationary central electrode, an electrical connection between said movable electrodes, abattery and an induction-coil, one situated in the connection leading to thecentral electrode and one in the connection between the movable electrodes, all substantially as specified and so as to alternate the greater part of the battery-current through the coil.

6. In atelephone-transmitter the combination with the diaphragm of three stationary electrode-buttons arranged in line therewith and the two nearest to the diaphragm being formed with perforations, two movable electrode-buttons arranged between the stationary buttons one on each side ofthe central button, a rod attached to the diaphragm and to thetwo movable buttons said rod passing through the perforated stationary buttons, granular conducting material situated between the adjacent faces of each electrodebutton and electrical connections as specified.

7. In a telephone-transmitter, substantially as specified, the combination with the electrode-box of the two stationary end electrodebuttons having electrical connections eX- IOO tending through the ends of the box and the sulated conductors one connected with each central stationary electrode-button havingan button.

electrical conductor extending through the 1 T side wan of the box. D II;- 5 S. In Ltelephone-transmitter,substantially as specified, the combination With the eleo- Vitnesses:

mode-box of the 'nwo movable electrode-but- A. H. RITTER,

tons and an actuating-rod embodying two n- D. STEWART. 

